Option 1 states that the Border Roads Organization (BRO) is responsible for the construction and maintenance of roads in strategically sensitive areas. This statement is indeed true as BRO is vital to the nation`s security, as their primary role is to ensure mobility to the armed forces by providing quality roads in border areas.

Option 2 suggests that the BRO undertakes snow clearance in high-altitude areas. This is also correct, as part of the BRO`s responsibilities in securing these strategic areas is to ensure that roads remain accessible throughout various weather conditions, including periods of heavy snowfall.

So, the correct answer is option 3 which suggests that both of these statements are correct. This reflects the wide range of roles that BRO covers, from building and maintaining access paths to ensuring they remain usable, especially in critical areas of national security.